Studies on the interrelationship between sugar transport and cellular metabolism will be continued: 1. The effect of hyperinsulinemia on glucose metabolism in suspensions of renal tubules of obese (Zucker) rats will be studied. Parameters measured: Oxidation of (U-14C)-C-glucose to 14CO2, and conversion to 14C-lactate; gluconeogenesis from (U-14C)-lactate and its oxidation to 14CO2. A comparison of some component enzymes involved in the metabolism of glucose in controls and obese rats may have to be carried out. 2. The effect of insulin, hypoinsulinemia (streptozotocin treated rats) and hyperinsulinemia (obese rats) on the transport of 3-0-methyl-glucose at the antiluminal face of renal tubules will be evaluated. 3. The effect of insulin on the transport and metabolism of sugars will be studied using renal epithelial cells grown in vitro (LLC-PK1 and MDCK cell lines). 4. The transport of 3-O-methyl-glucose and 2-deoxy-glucose in adipocytes from control and hyperinsulinemic (obese) rats will be examined.